The use of multiple optical channels, such as optical fibers, has become prevalent in applications ranging from communications to optical computing in response to a need for increased system bandwidth. In such multi-channel applications, a fiber array provides a desirable way for handling multiple optical fibers while attempting to effect control of positioning among the fibers. At the same time, providing precise positioning of a plurality of fiber cores relative to one another is critical to achieving acceptable system performance, since the fiber cores must be precisely registrable to other devices or fibers of the system. Without precise registration between the signal-carrying portion of the fiber, i.e., the fiber core, and other optical components, unacceptably large variation or degradation in optical performance may result. In this regard, mere movement or misalignment between fiber cores on the sub-micron scale may give rise to unacceptable performance degradation such as that caused by coupling loss and insertion loss. For example, single mode fibers presently in use typically have a core of 5 microns in diameter. Thus, movement or misalignment of the optical core by even 1 micron represents movement or misalignment by a substantial fraction of the core diameter.
A fiber array may find application in a number of optical computing and data communication applications, such as use as a component of a free-space optical switch. The need for optical switching to provide selective routing of information, without conversion of the optical signal into an electrical signal and back to an optical signal, is becoming increasingly important in optical data networks. To meet this need, a free space optical switch takes optical signals output from a first array of fibers and optically manipulates the signals so as to route the signals into a second array of fibers to effect a switching function. In such a system, routing can only be performed effectively when the relative locations among the fibers of an array are sufficiently precisely controlled. Moreover, as such systems include a greater number of fibers, the precision and tolerances with which each fiber must be positioned relative to neighboring fibers becomes more critical in order to achieve the overall required system performance.
Hence, for reasons such as these there remains a need for optical fiber arrays in which fibers can be precisely and reliably secured relative to one another and to a supporting substrate.